From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Test report on an automatic shock damper control system using a G.V. type governor on chassis M.Sch.3448.
| Identifier | ExFiles\Box 179b\2\ img206 | |
| Date | 16th December 1932 | |
| R.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to Sg.{Arthur F. Sidgreaves - MD} c. to Wf. c. to F.{Mr Friese} c. to SY. c. to DB.{Donald Bastow - Suspensions} c. to HdV. K.L.35. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} 2/DA.{Bernard Day - Chassis Design} 16.12.32. AUTOMATIC SHOCK DAMPER CONTROL BY G.V.TYPE GOVERNOR CHASSIS No. M.Sch.3448. This is now fitted to a 40/50 Car equipped with low rating springs and is working satisfactorily. The results are exceedingly good. Over the automatic range we can get a very soft ride at 30 M.P.H., with the fixed damper setting of about 40 lbs. ball pin load, and the governor will then raise the shock absorber load to 175 lbs. ball pin at 80 M.P.H. which is sufficient to improve the stability of the car considerably. At the higher loads, the new shock absorbers at once demonstrate their rigidity over the old type, as they produce an effect similar to Hartfords, whereas the spring in the levers of the old type shock absorbers prevented them ever being really effective for maximum damping. With an over-riding control fitted in series with the governor as in R.4/W.6.12.32. and set to increase the governor curve by 5 lbs./sq.in., the suspension seems to be stiffened up very satisfactorily at big M.P.H. so as to suit the type of owner who wishes to drive fast down winding lanes. Unfortunately, on the car to which the scheme is fitted, we are trying a Cadillac steering which is too low geared to enable one to control the car properly and get a good impression of its directional stability. However we are getting another set rapidly for a standard car. Naturally, however good the shock absorbers are, so long as we persist in using the road holding of Continental pattern on 110m/m.size tyres with low rating springs, we never shall have a car which is in any way comparable to present day D.I. rating. Nevertheless we believe the new M.E. scheme to be better than anything that has previously been done on controllable dampers. | ||